1. Field of the Invention
The present invention relates to an image decoding technology, and it particularly relates to method and apparatus for decoding coded image data.
2. Description of the Related Art
In the twentieth century, which was often called “The Century of Images,” a great variety of pictures and images were produced and put to use in movies, TV broadcasts and so forth. During the 1990's in particular, the widespread use of PCs (personal computers) and other information equipment, the popularization of digital cameras, color printers and so forth and the explosive increase in the use of the Internet accounted for deep infiltration of the culture of digital images into everyday life of ordinary people. Under these circumstances, coding and compression technologies, such as JPEG (Joint Photographic Expert Group) for still images and MPEG (Motion Picture Expert Group) for moving images, have been standardized so as to improve the facility of distribution and reproduction of the images through recording media, such as CD-ROM, and transmission media, such as networks and broadcasting waves. JPEG2000, which is an advanced version in the JPEG series, has already been announced, and the middle- to long-term targets for MPEG have already been worked out, too. Therefore, the on-going and future refinement of image processing technologies will without doubt lead us deeper into the world of digital images.
Standardization of image data formats promotes the exchanges of data between digital equipment. For example, the memory card about half the size of a name card enables data exchange between portable and other information equipment quite easily today. Data of images taken by a digital camera can be easily outputted by a high-definition color printer that supports the same data format. From now on, it is expected that there will be more and more scenes in which image data will be exchanged for use through various different types of equipment and devices.